A Polish cosmologist has determined that an entire universe could exist within every black hole in the cosmos.
The theory went as far as to suggest that if this were true then its possible our own universe is also inside a black hole and that the massive black holes at the centre of galaxies could be bridges to different universes.
Using an adaptation of Einstein's general theory of relativity, Nikodem Poplawski, of Indiana University, Bloomington, analysed the theoretical motion of particles entering a black hole.
http://www.telegraph.co.uk/science/spac ... ntist.html